JP2008538452A5

JP2008538452A5 -

Info

Publication number: JP2008538452A5
Application number: JP2008506975A
Authority: JP
Filing date: 2006-04-12
Publication date: 2009-04-30
Anticipated expiration: 2026-04-12

Claims

A light source (18) for generating light in the EUV region and a first optical system (19, 20, 21, 22, 23, 24) for illuminating the mask (25) with the light from the light source (18) And a second optical system (26, 27, 28, 29, 30) for imaging the mask (25) on the component (32), in particular a projection exposure system for microlithography. , At least one polarizing optical element (1) for the EUV region is disposed in a beam path between the light source (18) and the component member (32), and the at least one polarizing optical element is at least one reflection cone. A projection exposure system comprising surfaces (3, 7, 12, 14) and exerting a polarizing effect on the light emitted by the light source.

The polarizing optical element is
At least a predetermined polarization component of the EUV light incident on the region of the inclination angle α from 0 ° to the maximum inclination angle at which the conical surface (3) provides a polarizing action below the inclination angle α to the rotational symmetry axis of the conical surface. At least one cone (2) having an outer conical surface (3) that is reflective to the at least one concentrating EUV light reflected by the outer conical surface (3) of the cone (2) Projection exposure system according to claim 1, comprising two additional EUV light reflecting elements (4, 11, 13).

The polarizing optical element is
Reflected with respect to at least a predetermined polarization component of EUV light incident on the region of the inclination angle α from 0 ° to the maximum inclination angle below the inclination angle α to the rotational symmetry axis of the conical surface of another cone (6). Comprising at least one further cone (6) having an external conical surface (3)
Projection exposure system according to claim 1 or 2, wherein the bottom areas of both cones (2, 6) face each other and the rotational symmetry axes of both cone faces (3, 7) coincide.

The at least one further element (4) is formed as a hollow cylinder, its inner surface (5) is reflective, and the axis of rotational symmetry of the hollow cylinder is the at least one cone (2, 6). The projection exposure system according to claim 2, wherein the projection exposure system is arranged so as to coincide with the rotational symmetry axis.

At least one other reflective element of the at least one polarizing optical element is configured to receive EUV light incident on the region of the inclination angle α from 0 ° to the maximum inclination angle below the inclination angle α to the rotational symmetry axis of the conical surface. A projection exposure system having two inner conical surfaces (12, 14) that are reflective to at least a predetermined polarization component,
Both inner conical surfaces (12, 14) face each other, and the rotational symmetry axes of both inner conical surfaces (12, 14) are coincident,
The cone so that incident EUV light is first reflected by the polarizing outer cone surface (3), subsequently reflected by both inner cone surfaces (12, 14) and then reflected by the other outer cone surface. Projection exposure system according to claim 2 or 3, wherein the surfaces (3, 7, 12, 14) are arranged.

Projection exposure system according to claim 5, wherein the outer conical surfaces (3, 7) and the inner conical surfaces (12, 14) of the polarizing optical element have the same cone angle.

6. The projection exposure system according to claim 5, wherein the polarizing optical element has a cone angle of 45 [deg.].

A light source (18) for generating light in the EUV region and a first optical system (19, 20, 21, 22, 23, 24) for illuminating the mask (25) with the light from the light source (18) And a second optical system (26, 27, 28, 29, 30) for imaging the mask (25) on the component (32), in particular a projection exposure system for microlithography. , At least one polarizing optical element (1) for the EUV region is disposed in a beam path between the light source (18) and the constituent member (32), and the at least one polarizing optical element is
A substrate that is at least partially transparent to a first polarization state of EUV light incident below a predetermined tilt angle α;
A layer structure disposed on the substrate and having reflectivity with respect to a second polarization state of EUV light;
The polarizing optical element includes a mirror (15) having the layer structure, and acts as a polarizing beam splitter, and transmits a transmitted beam having a first polarization state and a mirror-reflected beam having a second polarization state. A projection exposure system in which

9. The projection exposure system according to claim 8, wherein the substrate and the layer structure of the polarizing optical element are arranged so as to have a transparent and reflecting optical function at an incident angle α of about 45 ° EUV light.

10. Projection exposure system according to claim 8 or 9, wherein the substrate has a thickness of less than 1 [mu] m, preferably a silicon substrate.

11. Projection exposure system according to claim 10, wherein the substrate of the polarizing optical element is arranged in a locally perforated carrier structure which is mechanically more stable than the substrate.

The projection exposure system according to any one of claims 8 to 11, wherein the layer structure comprises alternately continuous molybdenum layers and silicon layers.

The projection exposure system according to claim 12, wherein the layer structure has a plurality of layers alternately arranged.

14. Projection exposure system according to claim 13, wherein the polarizing optical element comprises less than 80 alternating layers, preferably about 40 alternating layers.

15. The layer thickness of the molybdenum layer of the polarizing optical element is 2,478 nm / cos α, and the layer thickness of the silicon layer of the polarizing optical element is 4,406 nm / cos α. Projection exposure system.

The projection exposure system according to any one of claims 8 to 15, wherein the polarizing optical element is arranged so that an intensity of a transmission component of EUV light is at least 10% of an intensity of a reflection component.

The projection exposure system according to claim 16, wherein the polarizing optical element is arranged so that the intensity of a transmission component of EUV light is at least 15% of the intensity of a reflection component.

18. The projection exposure system according to claim 17, wherein the polarizing optical element is arranged so that the intensity of a transmission component of EUV light is at least 20% of the intensity of a reflection component.

The layer structure of the polarizing optical element has at least one layer of non-uniform thickness, or
19. Projection according to any one of claims 8 to 18, wherein at least one of the layers of the layer structure has a surface exposed to an EUV light beam, the surface having several partial surfaces inclined relative to each other. Exposure system.

Method for producing a microstructured component (32), wherein the projection exposure system is at least partially manipulated by polarized EUV light to image the mask (25) on the photosensitive coating of the component (32) .

A fine-structured component (32) that images the mask (25) on the photosensitive coating of the component (32) with the aid of a projection exposure system operated in the EUV region and corrects the polarization state of the light used for this purpose. ).

A polarizing optical element for the EUV region, adapted to operate in the projection exposure system according to claim 1.

Comprising at least one component (2, 4, 6, 11, 13, 16, 17), wherein the action of said component on the polarization state of the light beam spreading spatially obliquely across the cross-section of the light beam The polarizing optical element according to claim 21, which is different.

In the case of a light beam that spatially spreads in the direction of propagation, it comprises at least one component (2, 4, 6, 11, 13, 16, 17) that forms a non-uniform polarization distribution across the cross section of the light beam. The polarizing optical element according to claim 21.